1. Field of the Invention
The present invention relates generally to portable vacuum cleaners, more particularly to, a vacuum cleaner capable of operating with both air and liquid.
2. Description of Related Art
Currently, there exists portable vacuum cleaners which pick up or vacuum solid or liquid material. These portable vacuum cleaners are frequently referred to as "wet-dry" vacuum cleaners. Commonly, such vacuum cleaners include an electric motor for imparting rotation to a fan to create a partial vacuum. The motor is typically connected by electrical wiring to a plurality of batteries acting as the power source to power the motor. The vacuum cleaner also includes a switch which provides for the coupling of electric power from the batteries to the motor. The vacuum cleaner further includes a charging circuit for removable connection to a battery charging unit for charging the batteries during a period of non-use of the vacuum cleaner.
One disadvantage of current portable or hand-held vacuum cleaners is that the switch may be left in an operable position when the vacuum cleaner is placed on the battery charging unit. As a result, the motor may operate while the batteries of the vacuum cleaner are charging. This prevents the batteries from receiving the maximum charge possible.
It is, therefore, an object of the present invention to prevent electrical power flow from the batteries to the motor if the switch is left in an operable position when the vacuum cleaner is placed on the battery charging unit to ensure that the batteries are always charging.